* fhandler_socket.cc (fhandler_socket::evaluate_events): Circumvent

	potential race condition.
	(fhandler_socket::recv_internal): Fix MSG_PEEK bug on blocking sockets
	and simplify recv loop.
	(fhandler_socket::send_internal): Only lock when changing wsock_events.

diff --git a/winsup/cygwin/ChangeLog b/winsup/cygwin/ChangeLog
index d697f89..5e3f337 100644 (file)
--- a/winsup/cygwin/ChangeLog
+++ b/winsup/cygwin/ChangeLog
@@ -1,5 +1,13 @@
 2006-07-31  Corinna Vinschen  <corinna@vinschen.de>
 
+       * fhandler_socket.cc (fhandler_socket::evaluate_events): Circumvent
+       potential race condition.
+       (fhandler_socket::recv_internal): Fix MSG_PEEK bug on blocking sockets
+       and simplify recv loop.
+       (fhandler_socket::send_internal): Only lock when changing wsock_events.
+
+2006-07-31  Corinna Vinschen  <corinna@vinschen.de>
+
        * autoload.cc: Drop LoadDLLprime for wsock32 since no wsock32 function
        is used anymore.  Drop all unused ws2_32.dll functions.  
 

diff --git a/winsup/cygwin/fhandler_socket.cc b/winsup/cygwin/fhandler_socket.cc
index be7f707..6a1cdd1 100644 (file)
--- a/winsup/cygwin/fhandler_socket.cc
+++ b/winsup/cygwin/fhandler_socket.cc
@@ -494,6 +494,7 @@ fhandler_socket::evaluate_events (const long event_mask, long &events,
                                  bool erase)
 {
   int ret = 0;
+  long events_now = 0;
 
   WSANETWORKEVENTS evts = { 0 };
   if (!(WSAEnumNetworkEvents (get_socket (), wsock_evt, &evts)))
@@ -502,6 +503,7 @@ fhandler_socket::evaluate_events (const long event_mask, long &events,
         {
          LOCK_EVENTS;
          wsock_events->events |= evts.lNetworkEvents;
+         events_now = (wsock_events->events & event_mask);
          if (evts.lNetworkEvents & FD_CONNECT)
            wsock_events->connect_errorcode = evts.iErrorCode[FD_CONNECT_BIT];
          UNLOCK_EVENTS;
@@ -511,7 +513,8 @@ fhandler_socket::evaluate_events (const long event_mask, long &events,
     }
 
   LOCK_EVENTS;
-  if ((events = (wsock_events->events & event_mask)) != 0)
+  if ((events = events_now) != 0
+      || (events = (wsock_events->events & event_mask)) != 0)
     {
       if (events & FD_CONNECT)
        {
@@ -1154,27 +1157,15 @@ fhandler_socket::recv_internal (WSABUF *wsabuf, DWORD wsacnt, DWORD flags,
   int evt_mask = FD_READ | ((flags & MSG_OOB) ? FD_OOB : 0);
 
   flags &= MSG_WINMASK;
-  if (flags & MSG_PEEK)
+  /* Note: Don't call WSARecvFrom(MSG_PEEK) without actually having data
+     waiting in the buffers, otherwise the event handling gets messed up
+     for some reason. */
+  while (!(res = wait_for_events (evt_mask | FD_CLOSE)))
     {
-      LOCK_EVENTS;
       res = WSARecvFrom (get_socket (), wsabuf, wsacnt, &ret,
                         &flags, from, fromlen, NULL, NULL);
-      wsock_events->events &= ~evt_mask;
-      UNLOCK_EVENTS;
-    }
-  else
-    {
-      do
-        {
-         LOCK_EVENTS;
-         res = WSARecvFrom (get_socket (), wsabuf, wsacnt, &ret,
-                            &flags, from, fromlen, NULL, NULL);
-         wsock_events->events &= ~evt_mask;
-         UNLOCK_EVENTS;
-       }
-      while (res && WSAGetLastError () == WSAEWOULDBLOCK
-            && !(res = wait_for_events (evt_mask | FD_CLOSE)))
-       ;
+      if (!res || WSAGetLastError () != WSAEWOULDBLOCK)
+       break;
     }
 
   if (res == SOCKET_ERROR)
@@ -1267,12 +1258,14 @@ fhandler_socket::send_internal (struct _WSABUF *wsabuf, DWORD wsacnt, int flags,
 
   do
     {
-      LOCK_EVENTS;
       if ((res = WSASendTo (get_socket (), wsabuf, wsacnt, &ret,
                            flags & MSG_WINMASK, to, tolen, NULL, NULL))
          && (err = WSAGetLastError ()) == WSAEWOULDBLOCK)
-        wsock_events->events &= ~FD_WRITE;
-      UNLOCK_EVENTS;
+        {
+         LOCK_EVENTS;
+         wsock_events->events &= ~FD_WRITE;
+         UNLOCK_EVENTS;
+       }
     }
   while (res && err == WSAEWOULDBLOCK
         && !(res = wait_for_events (FD_WRITE | FD_CLOSE)));